Table 1.
Genotypic characteristics of S. aureus bloodstream isolates stratified by agr functionality
| Genotype | No. (%) of isolates |
P valuea | |
|---|---|---|---|
| Dysfunctional agr | Functional agr | ||
| MRSA (n = 407) | 302 | 105 | |
| agr genotype | <0.001 | ||
| I | 29 (9.6) | 94 (89.5) | |
| II | 270 (89.4) | 6 (5.7) | |
| III | 2 (0.7) | 1 (1.0) | |
| ND | 1 (0.3) | 4 (3.8) | |
| SCCmec type | <0.001 | ||
| I | 2 (0.7) | 3 (2.9) | |
| II | 274 (90.7) | 8 (7.6) | |
| III | 15 (5.0) | 2 (1.9) | |
| IV | 10 (3.3) | 87 (82.9) | |
| NDb | 1 (0.3) | 5 (4.8) | |
| MLST | <0.001 | ||
| ST1 | 2 (1.9) | ||
| ST5 | 270 (89.4) | 6 (5.7) | |
| ST72 | 10 (3.3) | 86 (81.9) | |
| ST239 | 17 (5.6) | 1 (1.0) | |
| Otherc | 5 (1.7) | 10 (9.5) | |
| MSSA (n = 232) | 29 | 203 | |
| agr genotype | 0.024 | ||
| I | 10 (34.5) | 123 (60.6) | |
| II | 6 (20.7) | 26 (12.8) | |
| III | 10 (34.5) | 42 (20.7) | |
| IV | 6 (2.9) | ||
| ND | 3 (10.3) | 6 (2.9) | |
| MLST | 0.030 | ||
| ST1 | 3 (10.3) | 24 (11.8) | |
| ST5 | 5 (17.2) | 11 (5.4) | |
| ST30 | 7 (24.1) | 18 (8.9) | |
| ST72 | 3 (10.3) | 26 (12.8) | |
| ST188 | 4 (13.8) | 42 (20.7) | |
| Otherd | 7 (24.1) | 82 (40.4) | |
P values comparing the values for the two groups were determined with a two-sided Fisher exact test.
ND, not determined.
The other MLSTs were ST254 (2 isolates), ST291 (1 isolates), and ST89 (2 isolates) in the dysfunctional-agr group and ST101 (2 isolates), ST188 (1 isolate), ST199 (1 isolate), ST254 (2 isolates), ST6 (1 isolate), ST8 (2 isolates), and ND (1 isolate) in the functional-agr group.
The other MLSTs were ST6 (1 isolate), ST8 (1 isolate), ST59 (1 isolate), ST101 (1 isolate), ST378 (1 isolate), ST1153 (1 isolate), and ST1156 (1 isolate) in the dysfunctional-agr group and ST6 (18 isolates), ST8 (2 isolates), ST15 (11 isolates), ST25 (1 isolate), ST45 (1 isolate), ST59 (3 isolates), ST96 (1 isolate), ST97 (7 isolates), ST101 (3 isolates), ST121 (7 isolates), ST217 (1 isolate), ST513 (10 isolates), ST573 (1 isolate), ST580 (1 isolate), ST587 (3 isolates), ST630 (9 isolates), ST883 (1 isolate), ST1821 (1 isolate), and ST2238 (1 isolate) in the functional-agr group.